Viewing archive of Sunday, 16 April 2017
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2017 Apr 16 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 106 Issued at 2200Z on 16 Apr 2017IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z
Solar activity has been at very low levels for the past 24
hours. There are currently 0 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a chance for a C-class flares on days one, two, and three (17 Apr,
18 Apr, 19 Apr).
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed
reached a peak of 381 km/s at 16/1150Z. Total IMF reached 5 nT at
16/0540Z. The maximum southward component of Bz reached -4 nT at
16/0531Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 909 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at unsettled to minor storm levels on day one (17 Apr), quiet to
active levels on day two (18 Apr) and unsettled to active levels on day
three (19 Apr).
III. Event Probabilities 17 Apr to 19 Apr
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 16 Apr 075 Predicted 17 Apr-19 Apr 083/088/090 90 Day Mean 16 Apr 078
V. Geomagnetic A Indices
Observed Afr/Ap 15 Apr 005/004 Estimated Afr/Ap 16 Apr 007/011 Predicted Afr/Ap 17 Apr-19 Apr 014/020-013/015-013/018
VI. Geomagnetic Activity Probabilities 17 Apr to 19 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 40% | 40% |
| Minor storm | 20% | 20% | 20% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 20% | 25% | 25% |
| Major-severe storm | 55% | 55% | 60% |
All times in UTC
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